1984 Seaswirl OMC running rough

Celtichawk

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Re: 1984 Seaswirl OMC running rough

I will also attempt to drain gas put in my car :) and when I get all the new parts installed I will pump new gas into it. Hopefully this will fix the problem and if not then my next step timing, compression test, and lastly carb rebuild or replacement.
 

Howard Sterndrive

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Re: 1984 Seaswirl OMC running rough

Seloc is a general guide covering more than 500 engine/drive arrangements. Get the real manual.
change the anti-siphon valve- $10 part.
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Howard: Looking at my picture of the valve removed, the bottom portion that has the threads is actually a extra piece over top of the elbow piece with threads. Is that something easy to just find at a hardware store? I can find the elbow pieces and the anti-siphon valve, but that extra piece which screws into my tank and judging by why they put it on is that the elbow piece is smaller thread size than the opening on my tank.

Just thought I ask since I was having issues finding that piece. I will look at the store today.

Also is this something worth while?
033500.jpg

Lastly I will make arrangements to obtain a copy of the Factory Manual!
 

Bondo

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Re: 1984 Seaswirl OMC running rough

Howard: Looking at my picture of the valve removed, the bottom portion that has the threads is actually a extra piece over top of the elbow piece with threads. Is that something easy to just find at a hardware store? I can find the elbow pieces and the anti-siphon valve, but that extra piece which screws into my tank and judging by why they put it on is that the elbow piece is smaller thread size than the opening on my tank.

Just thought I ask since I was having issues finding that piece. I will look at the store today.

Also is this something worth while?


Lastly I will make arrangements to obtain a copy of the Factory Manual!

Ayuh,... In the picture is a 3/8" pipe, to 1/4" bushing, a 1/4" pipe street elbow, 'n the remains of the anti-siphon valve...

Yes, those are readily available at a hardware store...
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Okay eliminated anti-siphon valve only for test purposes and motor seemed to run better. I hit about 3k rpm and some hesitation, one time bogged down. All fuel filters replaced, new plugs, points new, distribute, rotor, etc. Cleaned flame arrested, so I have new fuel pickup coming Friday along with anti-siphon valve. I will install that and see hoe goes. I didn't change fuel yet but its not old unless by chance it has water then idk. Next step Carb rebuild but anyone else got any other ideas? I'll run her Friday under load in water and not muffed.

Let me know if any other ideas. I know 3k rpm is not right should be higher.
 

Howard Sterndrive

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Re: 1984 Seaswirl OMC running rough

Check that your timing advance weights and springs in your distributor are not all rusty and gunked up with old gummy residue (common issue)
The weights/springs are underneath the points plate.
I also don't see where you put new points in it. Points need to be replaced every year (that's in the manual)
Then, I would double check your ignition timing per this:
http://marinemechanic.com/site/page105.html
^that's NOT in the manual
If the distributor has ever been removed/reinstalled the odds of most techs getting it installed on the correct lobe are 50/50

Your engine should turn 4200-4600 and rpm. My 3.8's push my 175 Grew to 51mph, and my 185 Bayliner to 46 mph.
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

I spoke with original owner who said the points were changed, condenser, wires, and plugs. Judging by what I can see its been changed. I will however use that link as a guide for timing today and also check those weights. Do I just spray some electrical cleaner in there to clean or they need complete replacement?
 

Howard Sterndrive

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Re: 1984 Seaswirl OMC running rough

brake clean and a small tooth brush might do it. then some engine oil for lube.
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

brake clean and a small tooth brush might do it. then some engine oil for lube.

Okay here is a picture of the distributor under the metal plate. Guessing this is dirty but I can see it also has some kind of lube in there too.

What I found out today, I started motor, hooked up a timing light and what do you know I could not see the groove line up with 4 degrees BTDC, in fact it was no where in sight. So I adjusted distributor until I could get the goove to line up to the 4 degrees btdc. Gues what now, no power it will idle but idles low, and as soon as you apply any throttle it just dies. I would like to guess here that the distributor was removed and never placed in the correct position. So any major things to look for when doing so?

1. Mark old spot just incase but at the same time I suppose its wrong anyhow.
2. Pull valve cover off in order to see valves so when the #1 cylinder is TDC I can visually see valves.
3. Place rotor on distributor in the #1 wire before placing back into the shaft
4. Make sure the groove is on TDC? Then once distributor is placed back into the shaft I can fine tune the timing?

I know that may not be all the details but its what I gather so far. Any other ides? I don't have a dwell meter so I will be using feeler gauge for now until I can get motor started after I pull distributer and place back in then I will get to store this week and buy one.

20120918_165823.jpg

Attached is inside of distibutor under plate holding condenser and points. (Obviously! :)
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Howard: By the way your link shows a V6 Distributor so will that make any difference when trying to remove and install distributor?
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Okay here is the latest, I removed distributor, turned engine to get #1 cylinder to TDC. The harmonic balancer groove was set to 0. I made sure the rotor on distibtuor was facing the spark plug #1 terminal on cap. Placed distributor in and at 0 it would not drop in so I turned motor until it dropped in. Keeping the rotor and cap lined up.

Here is my question about that how is that #1 cylinder at TDC, if you have to move engine to get distributor to drop in? Would it be better to not turn motor and just move distributor in and out while turning until I find the spot to drop in making sure rotor and cap terminal #1 line up? Make any sense?

Well boat starts up, adjusted idle screw and mixture screws to two turn full turns out. Timing is set to 4 degress BTDC. Boat will idle now but, as I thottle up it will stall. Please help what did I do wrong? The only thing I did not do is use a dwell meter, but I did measure my points using a feeler gauge. Any chance I just need to set dwell, then timing and it should be good? Or is it possible that I was on exhaust TDC and not compression TDC?
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Same as the above, I attempted to go out and check timing again, distributor placement and all checks out. TDC of cylinder #1 so at this point I have no idea. Still will idle but will not take throttle. #1 Cylinder has a clean spark plug as they are brand new, the rest were coated with black almost charcoal deposits. Even the center piece inside spark plug was black in color. Odd, so at this point if I changed everything the only last tid bit thing I can think of is Carburetor issues. Either rebuild or purchase a new carburetor. I will check my local boat shops for a used one and hopefully test carburetor especially if they know there's works.

Any other takes on this. Again wills start and idle, timing set to 4 degress btdc but not throttle or dies.
 

Howard Sterndrive

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Re: 1984 Seaswirl OMC running rough

Okay here is the latest, I removed distributor, turned engine to get #1 cylinder to TDC. The harmonic balancer groove was set to 0. I made sure the rotor on distibtuor was facing the spark plug #1 terminal on cap. Placed distributor in and at 0 it would not drop in so I turned motor until it dropped in. Keeping the rotor and cap lined up.
you need to ensure #1 is on a compression stroke when you drop the distributor in. It may have been TDC exhaust stroke which would result in timing being 180 distributor degrees out. (360 crank degrees)
a 4 stroke engine brings the piston to TDC twice. It only fires the plug on compression.

to verify correct stroke, put your finger over the sparkplug hole while turning engine.

I've lost track too - did you ever compression test the engine? while you have plugs out - run a comp test
 

bruceb58

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Re: 1984 Seaswirl OMC running rough

Well boat starts up, adjusted idle screw and mixture screws to two turn full turns out. Timing is set to 4 degress BTDC. Boat will idle now but, as I thottle up it will stall. Please help what did I do wrong? The only thing I did not do is use a dwell meter, but I did measure my points using a feeler gauge. Any chance I just need to set dwell, then timing and it should be good? Or is it possible that I was on exhaust TDC and not compression TDC?
If the boat starts up and you were able to set timing, the engine was on the proper stroke. Engine wouldn't come close to running if you were 180 out. Check your dwell with a dwell meter and then re set the timing.

Make sure your spark plug wires are in the proper firing order. Very easy to cross them.

I agree with Howard that you need to do a compression check.
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

I managed to set timing was tough. Very touchy and timing mark jumps around easy so a little precise maneuvering and I got. Wasn't sure if that means my timing gears are worn?

Today I will get my father to turn key slightly while I place finger over #1 cylinder just to double check one more time and make sure rotor is facing #1 spark plug post.

Then I will dwell test it. Thanks let you know how things work.
 

bruceb58

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Re: 1984 Seaswirl OMC running rough

Today I will get my father to turn key slightly while I place finger over #1 cylinder just to double check one more time and make sure rotor is facing #1 spark plug post.
You don't need to worry about that, you have the distributor in the correct position.

The timing jumping around is a different story. It should be rock solid. You have new cap, rotor and spark plug wires on this thing? Are spark plugs gapped properly?

If timing is jumping around, its likely your dwell is jumping around as well and that could be caused by loose distributor shaft, faulty points and even a faulty condensor. You have new points and condensor too?

I noticed you took off the points plate. Did you get the advance weights put on properly?
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Okay Howard got the compression test done this afternoon, it was 120, 120, 120, 120. All even I know that is low but they even so hopefully that's good.is this okay or does it present another problem?

Managed to have my father place finger over cylinder one while I turned motor over. Pressure pops out, and my rotor right on with spark post #1. So we know distritbuter set right now just need to buy a dwell meter to test.
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Another quick question my timing plate shows 12, 8, 4, 2, 0 or TDC then 2, 4, 8. And on the plate it shows Before then After stamped. The before is to left of 0 and After is to right. So when it says 4 degrees BTDC that means on the before side right?
 

Celtichawk

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Re: 1984 Seaswirl OMC running rough

Where are plates located? All I did was remove two screws holding plate that had condenser and points on it. Looked under and took that photo then put it back on. So if there was something else then idk. I can check advance weights but not sure what those are.
 
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